Kids of older dads face greater risk of autism

Melbourne, Aug 31: It is well known that a woman’s chances of giving birth to a child with Down Syndrome increase with age. However, a new study has suggested that men should also consider their biological clocks when planning a family.

Australian researchers at the Brain Institute in Queensland have claimed that children born to older fathers are at significantly higher risk of developing autism and other brain disorders.

Professor John McGrath and his colleagues report that older fathers pass on a type of genetic mutation, which they develop as they age.

They had earlier reported that compared to men in their early 20s, the offspring of men over age 50 have a two-fold risk of getting schizophrenia or autism.

For the study, McGrath and his team used a mouse model to look at the genetics lurking behind this phenomenon.

They believe DNA from the sperm cells of older dads are more likely to develop specific mutations called CNVs than that from younger dads.

McGrath and his team looked at the DNA of offspring from older and younger male mice, mated with mothers of the same age, and tested for CNVs that only occurred in the offspring.

“We found more of these mutations in the offspring of older dads,” ABC Science quoted McGrath as saying.

The offspring also had a different shaped brain and different behaviour to those from younger fathers.

McGrath said the CNVs discovered have already been linked to brain disorders in humans.

“In fact one of the mutations we found was in a well known autism gene,” he said.